This study aimed to identify major dietary patterns and assess their association with the quality of life (QoL) among industrial workers at Isfahan Steel Company, Iran, in 2015. A total of 3,063 employees participated, and dietary data were collected using a validated food frequency questionnaire. Major dietary patterns were extracted using exploratory factor analysis, and QoL was assessed using the Euro-QoL five-dimension questionnaire. Latent class analysis classified participants based on QoL, and multivariable logistic regression evaluated the association between dietary patterns and QoL. Three dietary patterns were identified: western, healthy, and traditional. Participants were classified into high and low QoL classes. Key findings include: Lower adherence to the healthy dietary pattern increased the risk of being in the low QoL class, with those in the lowest tertile of healthy dietary intake having higher odds of being in the low QoL class (AOR: 1.51, 95% CI: 1.19–1.91). Low adherence to the traditional diet decreased the risk of belonging to the low QoL class (AOR: 0.70, 95% CI: 0.55–0.88).
Higher adherence to the western dietary pattern increased the risk of low QoL, but this was not statistically significant. The study concludes that higher adherence to a healthy diet and lower adherence to a traditional diet are associated with better QoL among manufacturing employees.